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UPB

Woodline Partners’s Upstream Bio Inc UPB Stock Holding History

Woodline Partners’s Portfolio UPB Stock Details UPB Fund Activity
Bought
Maintained
Sold
Quarter Market Value Status Shares Change in
Stake 		Trade Value Portfolio Weight Portfolio Position
2026
Q1 		$7.48M Buy
831,481
+71,229
+9% +$1.28M 0.03% 579
2025
Q4 		$20.6M Buy
760,252
+158,000
+26% +$3.93M 0.08% 305
2025
Q3 		$11.3M Buy
602,252
+44,000
+8% +$684K 0.05% 415
2025
Q2 		$6.13M Buy
558,252
+1,189
+0.2% +$11K 0.03% 523
2025
Q1 		$3.41M Buy
557,063
+30,552
+6% +$292K 0.02% 589
2024
Q4 		$8.66M Buy
+526,511
New +$11.8M 0.06% 379

Other funds holding UPB

Fidelity Investments
Fidelity Investments Boston, Massachusetts $1.9T AUM 41.92% 1-Year Est. Return
O
OrbiMed New York $5.05B AUM 125.28% 1-Year Est. Return
BlackRock
BlackRock New York $5.72T AUM 30.48% 1-Year Est. Return
DC
Decheng Capital Menlo Park, California $661M AUM 299.97% 1-Year Est. Return
ES
Enavate Sciences Menlo Park, California $352M AUM 220.14% 1-Year Est. Return
VCM
Vanguard Capital Management Malvern, Pennsylvania $4.04T AUM
YIH
Y-Intercept (HK) Hong Kong $5.05B AUM 17.89% 1-Year Est. Return
Federated Hermes
Federated Hermes Pittsburgh, Pennsylvania $61.5B AUM 30.7% 1-Year Est. Return
Geode Capital Management
Geode Capital Management Boston, Massachusetts $1.61T AUM 30.72% 1-Year Est. Return
Millennium Management
Millennium Management New York $240B AUM 35.51% 1-Year Est. Return

Woodline Partners's UPB Position: Q1 2026 in Review

Woodline Partners increased its Upstream Bio Inc (UPB) stake by 9.4% in Q1 2026, buying an estimated $1.28M and bringing the position to 831,481 shares worth $7.48M. The position accounts for 0.03% of the portfolio, ranked #579.

Woodline Partners first reported a position in UPB in Q4 2024 and has held it in 6 quarters since. The position peaked at $20.6M in Q4 2025. 140 funds tracked by Wall St. Rank hold UPB as of Q1 2026.

  • Woodline Partners held 831,481 shares of Upstream Bio Inc worth $7.48M as of Q1 2026.
  • Woodline Partners bought 71,229 Upstream Bio Inc shares in Q1 2026, an estimated $1.28M.
  • Upstream Bio Inc made up 0.03% of Woodline Partners's portfolio in Q1 2026, its #579 holding.
  • Woodline Partners first reported a position in Upstream Bio Inc in Q4 2024 and has held it in 6 quarters since.
  • Woodline Partners's Upstream Bio Inc position peaked at $20.6M in Q4 2025.
  • 140 funds tracked by Wall St. Rank held Upstream Bio Inc as of Q1 2026.

Based on Woodline Partners's 13F filing for Q1 2026, filed 15 May 2026.